Origin of Species Variorum

←Subtitle not present 1859 1860 1861 Analogical Resemblances. — 1866 1869 1872

→ which is a pachydermatous animal, and the 1859 1860 1861 1866 1869

and 1872

→ mammals 1859 1860 1861 1866 1869

two orders of mammals 1872

↑ 2 blocks not present in 1859 1860 1861 1866 1869; present in 1872

So is the resemblance between a mouse and a shrew-mouse (Sorex), which belong to different orders; and the still closer resemblance, insisted on by Mr. Mivart, between the mouse and a small marsupial animal (Antechinus) of Australia. These latter resemblances may be accounted for, as it seems to me, by adaptation for similarly active movements through thickets and herbage, together with concealment from enemies.

→ thickened stems 1859 1860 1861 1866 1869

strikingly similar shape 1872

→ common and 1859 1860 1861 1866 1869

body in the improved breeds of the Chinese and common pig, which are descended from distinct species; and in the similarly thickened stems of the common and specifically distinct 1872

→ very distinct animals. 1859 1860 1861 1866

widely distinct animals. 1869

widely different animals. 1872

→ class or order 1859 1860 1861

class or one order 1866 1869

group 1872

Geographical distribution may sometimes be brought usefully into play in classing large

~~and widely-distributed~~

and widely-distributed

genera, because all the species of the same genus, inhabiting any distinct and isolated region,

are

have

in all probability descended from the same parents. →

We can understand, on

the above

these

views, the very important distinction between real affinities and analogical or adaptive resemblances. Lamarck first called attention to this

subject,

distinction,

and he has been ably followed by Macleay and others. The

resemblance

resemblance,

in the shape of the body and in the fin-like anterior

limbs

limbs,

between

~~the~~

the

dugons,

dugongs

dugong,

→which is a pachydermatous animal, and the

whales,

whale,

and between

~~both~~

both

these →mammals and fishes,

are

analogical. ↑ Amongst insects there are innumerable

in- stances:

similar instances;

instances:

thus Linnæus, misled by external appearances, actually classed an homopterous insect as a moth. We see something of the same kind even

with

our domestic varieties, as in the →thickened stems of the →common and

Swedish

swedish

turnip. The resemblance

between

the greyhound and

the racehorse

racehorse

is hardly more fanciful than the analogies which have been drawn by some authors between →very distinct animals. On

the

view of characters being of real importance for classification, only in so far as they reveal descent, we can clearly understand why analogical or adaptive

characters,

character,

although of the utmost importance to the welfare of the being, are almost valueless to the

systematists.

systematist.

For animals, belonging to two most distinct lines of descent, may

have

readily

have become

become

adapted to similar conditions, and thus

have assumed

assume

a close external resemblance; but such resemblances will not reveal— will rather tend to conceal their

blood-relationship.

~~their~~

~~proper~~

~~lines~~

~~descent.~~

We can

thus also

also

thus understand

understand

the apparent paradox, that the very same characters are analogical when one →class or order is compared with another, but give true affinities when the members of